New feature: removing element attribute from DB

Signed-off-by: selmeci <selmeci.roman@gmail.com>
Added removing for element attribute

Merge branch 'element-attribute-service' into
element-attribute-service-client

Conflicts:
	src/com/infones/edocu/types/element_attribute/core.clj

Signed-off-by: selmeci <selmeci.roman@gmail.com>
Merge branch 'element-attribute-service-client' into element-type-service